What to do if the ABS does not work

A permanently lit ABS indicator indicates that the system is damaged and you need to visit a service center. But we can carry out the initial diagnosis ourselves.

A permanently lit ABS indicator indicates that the system is damaged and you need to visit a service center. But we can carry out the initial diagnostics ourselves, because the malfunction can be easily detected.

The ABS warning light should come on every time the engine is started and then should go out after a few seconds. If the indicator is on all the time or lights up while driving, this is a signal that the system is out of order.

You can continue driving, because the brake system will work as if the ABS did not exist. Just remember that during emergency braking, the wheels can lock up and, as a result, there will be no controllability. Therefore, the fault should be diagnosed as soon as possible.

The ABS system consists mainly of electrical sensors, a computer and, of course, a control module. The first thing we should do is check the fuses. If they are OK, the next step is to check the connections, especially on the chassis and wheels. Next to each wheel there is a sensor that sends information about the speed of rotation of each wheel to the computer.

For sensors to work properly, two factors must be met. The sensor must be at the correct distance from the blade and the gear must have the correct number of teeth.

It may happen that the joint will be without a ring and then it needs to be pierced from the old one.

During this operation, damage or improper loading may occur and the sensor will not collect wheel speed information. Also, if the joint is chosen incorrectly, the distance between the disk and the sensor will be too large and the sensor will not "collect" signals, and the computer will consider this an error. The sensor can also send erroneous information if it gets dirty. This mainly applies to SUVs. In addition, a sensor resistance that is too high, for example due to corrosion, can lead to a malfunction.

There are also damage (abrasion) of cables, especially in cars after accidents. ABS is a system on which our safety depends, so if the sensor or cable is damaged, it should be replaced with a new one.

Also, the indicator will be on if the entire system is working and wheels of different diameters are on the same axle. Then the ECU reads the difference in wheel speed all the time, and this condition is also signaled as a malfunction. In addition, driving with the handbrake applied may cause the ABS to disengage.